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Nighttime humidity

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    Nighttime humidity

    Happy Labor Day folks!

    First week of flower and humidity measuring low 60s just before light comes on. During 12 on it’s in the low 50s.

    GWE recommends maintaining humidity levels at 40-50% during flower, while other sources suggest up to 65% is within range.

    Couple Qs:

    Will RH increase as the buds develop?

    When does bud rot start to be a risk?

    Thanks for your input. I know what VPD stands for but that’s the extent of my knowledge lol.

    BioCanna nutrient line, Canna BioTerra coco, Viparspectra XS2000 240w LED, 3 gallon fabric pots, 32x32x63” tent in basement.

    I've been growing since Hendrix's Axis album and I keep my grow room when flowering between 40-48% HR also to control it I use a dehumidifier. Remember if the humidity is too high you may end up with bud rot.


    Light: Viparspectra P2000, Viparspectra P1500, Viparspectra XS2000, KingLed 1500
    Medium: organic, Fafard perlite, Fafard Urban Garden organic mix, Organic compost shrimps.
    Nutrients: Alaskan Fish, Advanced Nutrients Big Bud, Advanced Nutrients Ancient Earth, Advanced Nutrients Sensi Cal Mag Xtra
    Full auto grow
    Grow room : 8X12X10, 2 industrial fans, 1 dehumidifier, 1 Vivosun carbon filter & controller
    6 AK-47 autos from Serious Seeds, 1 Neville Haze Ryder from WOS and 1 Larry Lemon OG auto from Seedsman


    • Cheeba
      Cheeba commented
      Editing a comment
      Cheers. It’s Now below 50 after half a light cycle, I’ll check again before light comes on again. Added a small floor fan to improve intake, ive been using a cheap 4” exhaust tan and hope that will do the trick.

      Thanks and I enjoy your thai bud photos.

    Conditions have stabilized somewhat after plugging in a big ole dehumidifier near tent. RH reduces nicely but temp increased. Some fluctuations as I dialed it in, latest readings are RH 40-55 and temp 70-81 for past 24 hours. Basement.

    Feeling good going into week 2!

    BioCanna nutrient line, Canna BioTerra coco, Viparspectra XS2000 240w LED, 3 gallon fabric pots, 32x32x63” tent in basement.


      Low 60s is where problems can arise. A good circulation shpuld combat the issue well. My flowering stage was always in the 50-58 RH range. It did get to 80 before and I freaked out. Never water a whole gallon with lights on then zip the tent up. I learned my lesson. Luckily, no nuds were harmed.
      Ask questions, take notes, and check your pH regularly. 😌

      2 x 2 x 4 Tent
      300W full-spectrum light

      MiracleGro soil (0.06 - 0.02 - 0.02)
      Humboldts Secret Calmag & Iron (2-0-0)
      FlowerFuel (0-34-32)


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